Market Segment:
Professional motocross and off-road racing.
Competitors:
Honda CRF250R, KTM 250 SX-F, Kawasaki KX250F, Suzuki RM-Z250.
Engine Type:
Liquid-cooled, four-stroke, DOHC, four-valve single-cylinder.
Suspension Technology:
KYB Speed Sensitive System (SSS) front forks and KYB rear shock.
Performance Focus:
Lightweight design and potent power delivery for competitive racing.
Target Audience:
Motocross racers, off-road enthusiasts, and DIY mechanics.
Engine:
Complete engine teardown, rebuild, inspection, and troubleshooting for the 250cc four-stroke engine.
Transmission:
Disassembly, inspection, and repair of the gearbox and clutch assembly.
Suspension:
Front forks (KYB Speed Sensitive System - SSS), rear shock absorber (KYB), including oil changes, seal replacement, and adjustments.
Brakes:
Front and rear brake systems, including hydraulic components, pad replacement, fluid bleeding, and caliper service.
Electrical:
Ignition system, lighting, charging system, wiring diagrams, and troubleshooting of electrical components.
Fuel System:
Carburetor (Keihin FCR-MX37) tuning, cleaning, and component replacement.
Cooling System:
Radiator, hoses, and coolant maintenance.
Exhaust System:
Exhaust pipe and muffler maintenance.
Frame And Bodywork:
Chassis, subframe, fuel tank, seat, body panels, and handlebars.
Maintenance:
Regular maintenance tasks, lubrication, inspections, and replacement intervals.
Troubleshooting:
Diagnostic procedures for common problems and fault finding.
Repair:
Step-by-step instructions for component repair and replacement.
Rebuild:
Detailed procedures for complete engine and component rebuilds.
Specifications:
Torque specifications, clearances, and adjustment data for all components.
Diagnostics:
Fault codes, testing procedures, and diagnostic flowcharts.
Depth:
Comprehensive; covers basic maintenance to complete engine and chassis overhauls.
Visuals:
Includes photographs and detailed part diagrams for clarity.
Engine Type:
Liquid-cooled, four-stroke, DOHC, four-valve, single-cylinder
Bore X Stroke:
77.0 mm x 53.6 mm
Compression Ratio:
12.8:1
Horsepower:
Approx. 37.7 hp @ 11,000 rpm (claimed, may vary by region/dyno)
Torque:
Approx. 26.7 Nm (19.7 lb-ft) @ 8,500 rpm (claimed, may vary by region/dyno)
Carburetor:
Keihin FCR-MX37 with Accelerator Pump
Fuel Type:
Unleaded gasoline, octane rating 91 or higher
Oil Type:
Yamalube 4 (or equivalent) SAE 10W-40 API SG or higher
Ignition System:
CDI (Capacitor Discharge Ignition)
Cooling Method:
Liquid-cooled
Transmission Type:
Constant mesh 5-speed
Clutch Type:
Wet, multi-disc, cable-actuated
Gear Ratios:
1st: 2.615, 2nd: 1.941, 3rd: 1.571, 4th: 1.333, 5th: 1.150
Final Drive:
Chain drive (RK 520)
Safety Ratings:
Not applicable (Competition Motorcycle)
Brakes:
Hydraulic disc brakes front and rear.
Suspension:
KYB SSS forks and KYB shock absorber provide advanced damping and adjustability.
Chassis:
Strong aluminum frame and subframe for rigidity and rider control.
Ergonomics:
Designed for rider comfort and control during demanding off-road use.
Oil Change Frequency:
Every 10-15 hours of riding or as per manual recommendations.
Air Filter Cleaning:
After every few rides or more frequently in dusty conditions.
Spark Plug Inspection:
Every 20-30 hours of riding.
Valve Clearance Check:
Every 30-40 hours of riding.
Engine Oil:
Yamalube 4 (or equivalent) SAE 10W-40 API SG or higher
Coolant:
Permanent type antifreeze coolant with a 50/50 mix of distilled water.
Brake Fluid:
DOT 4 hydraulic brake fluid.
Fork Oil:
Yamaha Fork Oil G10 (or equivalent SAE 0W-20 weight)
Clutch Wear:
Clutch plates can wear relatively quickly under hard racing conditions; regular inspection and adjustment are recommended.
Carburetor Tuning:
The FCR-MX carburetor may require periodic adjustments due to altitude and temperature changes.
Piston Ring Wear:
Regular inspection of piston rings and cylinder bore is advised, especially after extensive use.
Brand Focus:
Yamaha has a long and successful history in motorcycle racing, particularly in motocross with its YZ line.
Yz250F Development:
The YZ250F has consistently evolved with advancements in engine technology, suspension, and chassis design since its inception.
2010 Updates:
The 2010 model benefited from refinements to the engine and suspension, building upon previous successful iterations.
Manufacturing Location:
Japan
Motocross Reputation:
The YZ250F platform is renowned in motocross for its potent engine, excellent suspension, and competitive chassis.
Manual Value:
This manual is invaluable for owners looking to maintain, troubleshoot, and repair their 2010 Yamaha YZ250F to factory specifications.
